[Info-vax] BACKUP - Why have these files been selected ?

[Syltrem]

Bon matin

Is it me or something's fishy ?
It seems to me that the below files should not have been backed up, since 
the MODIFIED date is less than the BACKUP date

$ direr IVA_BKP$EXTERNAL:[IAFBKP...]*.*;/dat=(c,m,b)

Directory IVA_BKP$EXTERNAL:[IAFBKP]

CogStartup-IAFC.xml;1
                     17-MAY-2010 16:28:54.20  23-NOV-2010 21:04:33.07 
27-OCT-2011 09:39:38.60
IVACOIAFA.BKF;228    13-OCT-2010 21:23:33.11  13-OCT-2010 21:23:42.23 
27-OCT-2011 09:39:38.60
IVACOIAFB.BKF;222    12-OCT-2010 21:22:51.19  12-OCT-2010 21:23:03.40 
27-OCT-2011 09:39:38.60
IVACOIAFC.BKF;1      19-MAY-2010 10:24:42.97  23-NOV-2010 21:05:33.75 
27-OCT-2011 09:39:38.60

Total of 4 files.
$ backo    IVA_BKP$EXTERNAL:[IAFBKP]*.* /Since=Backup/Modified syl:f.bck/sav 
/log/reco
%BACKUP-S-COPIED, copied IVA_BKP$EXTERNAL:[IAFBKP]CogStartup-IAFC.xml;1
%BACKUP-S-COPIED, copied IVA_BKP$EXTERNAL:[IAFBKP]IVACOIAFA.BKF;228
%BACKUP-S-COPIED, copied IVA_BKP$EXTERNAL:[IAFBKP]IVACOIAFB.BKF;222
%BACKUP-S-COPIED, copied IVA_BKP$EXTERNAL:[IAFBKP]IVACOIAFC.BKF;1
%BACKUP-I-STARTRECORD, starting backup date recording pass at 27-OCT-2011 
09:40:11.68

btw I used a phony 5th letter on the command to rule out using symbols...

Thanks for your comments
Syltrem